@Wintersun Not quite sure what you mean but it looks like you want something like this: It functions the same as your normal grid. When you create primitives they will be aligned to that grid, you can snap to it etc. When your done with it you can reactivate the homegrid or just delete it.
You have to build the "heart" out of those extruded shapes, this mean that you first make them tracing the reference, then, with the edges you got, you make the rest of the mask. With your method you're pretending that the topology will follow another shape just because you made some cuts.